CN109659605B - Self-healing polymer electrolyte matrix and preparation method thereof, self-healing polymer electrolyte, lithium ion battery and application thereof - Google Patents

Abstract

The invention provides a self-repairing polymer electrolyte matrix and a preparation method thereof, a self-repairing polymer electrolyte, a lithium ion battery and applications thereof, belonging to the technical field of self-repairing polymer electrolytes. The present invention provides a self-healing polymer electrolyte. The matrix of the self-repairing polymer electrolyte includes inorganic nano-additives, self-repairing polyurethane and other polymers; wherein, the inorganic nano-additives and other polymers are grafted on the self-repairing polyurethane; self-repairing Polyurethanes are obtained by the Diels‑Alder reaction. The reversible effect of furan-maleimide structure in self-healing polyurethane makes the self-healing polymer electrolyte matrix have good self-healing ability; the polymer electrolyte makes the self-healing polymer electrolyte matrix have good ionic conductivity; inorganic nano-additives Active sites are provided, enabling the polymer to easily form a three-dimensional cross-linked structure, which further improves the ionic conductivity.

Description

Self-healing polymer electrolyte matrix and preparation method thereof, self-healing polymer electrolyte quality, lithium-ion batteries and their applications

technical field

The invention belongs to the technical field of self-repairing polymer electrolytes, and in particular relates to a self-repairing polymer electrolyte matrix and a preparation method thereof, a self-repairing polymer electrolyte, a lithium ion battery and applications thereof.

Background technique

Due to the advantages of high energy density, small size and long life, lithium-ion batteries have broad application prospects as energy storage devices in portable electronic devices, electric vehicles and other fields. With the rapid development of wearable electronic devices, the research and development of lithium-ion batteries with good flexibility has become a focus of attention. Due to the complexity of the use environment, people put forward higher requirements for the safety and reliability of flexible lithium-ion batteries, because various external force stimuli and physical damage, such as bending and torsion, are inevitably encountered in practical applications. Physical damage such as , stretching and shearing may lead to irreversible functional obstacles of energy storage devices, and even lead to severe environmental and safety problems such as electrolyte leakage and explosion.

At present, there are few research reports on self-healing polymer electrolytes at home and abroad. The main research and development are self-healing hydrogel electrolytes used in aqueous supercapacitors and aqueous lithium-ion batteries. Although it has good self-healing performance, the operating voltage window of aqueous polymer electrolytes is limited (less than 2 V), resulting in low energy density of energy storage devices.

In view of this, the present invention is proposed.

SUMMARY OF THE INVENTION

The first object of the present invention is to provide a self-healing polymer electrolyte matrix; the self-healing polymer electrolyte matrix can be used to prepare a self-healing polymer electrolyte with high working voltage, excellent electrochemical performance and good self-healing performance, and can Overcome the above problems or at least partially solve the above technical problems.

The second object of the present invention is to provide a method for preparing the above-mentioned self-healing polymer electrolyte matrix.

The third object of the present invention is to provide a self-healing polymer electrolyte, including the above-mentioned self-healing polymer electrolyte matrix.

The fourth object of the present invention is to provide a method for preparing the above-mentioned self-healing polymer electrolyte.

The fifth object of the present invention is to provide a lithium ion battery, comprising the above self-healing polymer electrolyte; the lithium ion battery has good flexibility, self-healing performance and high energy density.

A sixth object of the present invention is to provide the application of the above-mentioned lithium ion battery in electronic equipment, electric tools or electric vehicles.

According to a first aspect of the present invention, there is provided a self-healing polymer electrolyte matrix, the self-healing polymer electrolyte matrix comprising inorganic nano-additives, self-healing polyurethane and other polymers;

Wherein, the inorganic nano-additive and other polymers are grafted on the self-healing polyurethane;

The self-healing polyurethane is obtained by Diels-Alder reaction;

Preferably, the Diels-Alder reaction is a furan/maleimide Diels-Alder cycloaddition reaction;

Preferably, a furan ring graft-modified polyurethane is obtained by grafting a furan derivative on the polyurethane, and then a self-healing polyurethane is obtained by the Diels-Alder reaction between the furan ring graft-modified polyurethane and the maleimide derivative;

Wherein, the end groups of the polyurethane include isocyanate groups.

Preferably, the functional group of the furan derivative includes at least one of amino group, hydroxyl group and carbamate;

Preferably, the furan derivatives include 2,5-furandimethanol, trifuryldiol, furfuryl alcohol, furfurylamine, furan ring-terminated polyurethane prepolymer and 1,6-hexamethylene-bis(2 - at least one of furanyl methyl carbamate), preferably 2,5-furan dimethanol and/or trifuryl diol;

Preferably, the maleimide derivatives include polymaleimide and/or hydroxyl-containing monomaleimide, preferably bismaleimide and/or hydroxyl-containing monomaleimide imine;

Preferably, the maleimide derivatives include N-hydroxyethylmaleimide, N,N'-(4,4'-methylenediphenyl)bismaleimide, M At least one of -600-maleamide, D-400-maleamide and T-403-maleamide, preferably N-hydroxyethylmaleimide and/or N,N'-(4 , 4'-methylene diphenyl) bismaleimide.

Preferably, the inorganic nano-additives include at least one of graphene oxide, carbon nanotubes, nano-Al ₂ O ₃ , nano-SiO ₂ and nano-TiO ₂ , preferably graphene oxide;

And/or, the other polymer comprises any one of PVDF, PVDF-HFP, PEO or PAN, or a composite material comprising any of the foregoing materials, preferably PVDF-HFP;

Preferably, the mass fraction of the inorganic nano-additive is 0%-10%, preferably 0.5%-5%, more preferably 0.8%-1.5%;

Preferably, the mass fraction of the self-healing polyurethane is 30%-60%, preferably 40%-50%;

Preferably, the mass fraction of the other polymers is 30%-60%, preferably 40%-50%.

According to a second aspect of the present invention, there is provided a method for preparing the above-mentioned self-healing polymer electrolyte matrix, comprising the following steps:

Inorganic nano-additives and other polymers are grafted on the self-healing polyurethane to obtain a self-healing polymer electrolyte matrix.

Preferably, the preparation method of the self-healing polymer electrolyte matrix comprises the following steps:

(a) dissolving the inorganic nano-additive in an organic solvent, then adding diisocyanate, and reacting to obtain a modified inorganic nano-additive;

(b) adding a bishydroxy compound to the solution obtained in step (a), and obtaining a polyurethane grafted with an inorganic nano-additive after the reaction;

(c) adding a furan derivative to the step (b), so that the furan derivative is grafted on the polyurethane obtained in the step (b);

(d) adding the maleimide derivative to the step (c), so that the maleimide derivative and the furan derivative undergo Diels-Alder reaction to obtain a self-repairing polyurethane with dynamic covalent bonds;

(e) dissolving other polymers in an organic solvent, and then adding them to the solution in step (d), so that other polymers are grafted on the self-healing polyurethane obtained in step (d), and coated on the surface of the substrate, and after removing the solvent , to obtain a self-healing polymer electrolyte matrix;

Preferably, in step (a), the organic solvent includes an amide organic solvent, preferably N,N-dimethylformamide;

And/or, in step (a), the diisocyanate comprises 4,4'-methylenebis(phenyl isocyanate), toluene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, At least one of hexamethylene diisocyanate and lysine diisocyanate, preferably 4,4'-methylenebis(phenyl isocyanate);

And/or, in step (a), the temperature of the reaction is 75-95°C, the time of the reaction is 2-4h, and the gas atmosphere of the reaction is nitrogen;

And/or, in step (a), the feed ratio of the inorganic nano-additive, organic solvent and diisocyanate is 0-22:40-60:6-10mg/mL/mmol, preferably 20:50:8mg/mL /mmol;

And/or, in step (b), the dihydroxy compound includes polyether polyol, preferably polytetrahydrofuran diol, more preferably polytetrahydrofuran diol with a number average molecular weight of 1500-2500;

And/or, in step (b), the temperature of the reaction is 75-95 ° C, the time of the reaction is 2-4h, and the gas atmosphere of the reaction is nitrogen;

And/or, in step (b), the molar ratio of the dihydroxy compound to diisocyanate is 1:1.8-2.5, preferably 1:2;

And/or, in step (c), the temperature of the grafting is 75-95 ° C, the time of the grafting is 2-4h, and the gas atmosphere of the grafting is nitrogen;

And/or, in step (c), the molar ratio of the furan derivative to the diisocyanate is 6-6.5:8, preferably 6.25:8;

And/or, in step (d), the temperature of the reaction is 75-95 ° C, the time of the reaction is 12-38h, and the gas atmosphere of the reaction is nitrogen;

And/or, in step (d), the molar ratio of the maleimide derivative to the furan derivative is 4-4.5:6-6.5, preferably 4.2:6.25;

And/or, in step (e), the organic solvent includes an amide organic solvent, preferably N,N-dimethylformamide;

And/or, in step (e), the temperature of the grafting is 60-100°C, and the time of the grafting is 1-12h;

And/or, in step (e), the weight ratio of the other polymer to the self-healing polyurethane is 30-60:30-60, preferably 40-50:40-50.

According to a third aspect of the present invention, a self-healing polymer electrolyte is provided, comprising the above-mentioned self-healing polymer electrolyte matrix or the self-healing polymer electrolyte matrix obtained by the above preparation method, an electrolyte salt and a solvent.

Preferably, the electrolyte salt includes lithium salt, preferably lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium acetate, lithium salicylate, lithium acetoacetate, lithium carbonate, lithium trifluoromethanesulfonate, dodecane at least one of lithium sulfate, lithium citrate, lithium bis(trimethylsilyl)amide, lithium hexafluoroarsenate and lithium trifluoromethanesulfonimide, more preferably lithium hexafluorophosphate;

Preferably, the solvent includes an organic solvent or an ionic liquid;

Preferably, the organic solvent includes at least one of ester solvents, sulfone solvents, amide solvents, ether solvents and nitrile solvents;

Preferably, the ester solvent includes propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, ethyl methyl carbonate, butylene carbonate, dipropyl carbonate, methyl propyl carbonate, dibutyl carbonate Ester, methyl butyl carbonate, methyl isopropyl carbonate, methyl ester, methyl formate, methyl acetate, fluoroethylene carbonate, methyl propionate, ethyl propionate, ethyl acetate, γ-butyrolactone, At least one of ethylene sulfite, propylene sulfite, dimethyl sulfite and diethyl sulfite, preferably propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate and ethyl methyl carbonate at least one of the esters;

Preferably, the sulfone solvent includes dimethyl sulfone;

Preferably, the amide solvent includes N,N-dimethylacetamide;

Preferably, the ether solvent includes tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, dimethoxymethane, 1,2 - at least one of dimethoxyethane, 1,2-dimethoxypropane, triethylene glycol dimethyl ether, dimethyl ether and crown ether;

Preferably, the ionic liquid comprises 1-ethyl-3-methylimidazole-tetrafluoroborate, 1-ethyl-3-methylimidazole-hexafluorophosphate, 1-ethyl-3-methyl Imidazole-bistrifluoromethanesulfonimide salt, 1-propyl-3-methylimidazole-tetrafluoroborate, 1-propyl-3-methylimidazole-hexafluorophosphate, 1-propyl -3-Methylimidazole-bis-trifluoromethanesulfonimide salt, 1-butyl-1-methylimidazole-hexafluorophosphate, 1-butyl-1-methylimidazole-tetrafluoroborate , 1-butyl-1-methylimidazole-bis-trifluoromethylsulfonimide salt, N-butyl-N-methylpyrrolidine-bis-trifluoromethylsulfonimide salt, 1-butyl -1-Methylpyrrolidine-bis-trifluoromethylsulfonimide salt, N-methyl-N-propylpyrrolidine-bis-trifluoromethylsulfonimide salt, N-methyl, propylpiperidine - at least one of bis-trifluoromethanesulfonimide salt and N-methyl, butylpiperidine-bis-trifluoromethanesulfonimide salt;

Preferably, the concentration of the electrolyte salt in the electrolyte is 0.1-10 mol/L, preferably 1 mol/L.

According to a fourth aspect of the present invention, there is provided a method for preparing the above-mentioned self-healing polymer electrolyte, comprising the following steps:

The self-healing polymer electrolyte matrix is immersed in a solvent containing electrolyte salt and adsorbed to saturation to obtain a self-healing polymer electrolyte.

According to a fifth aspect of the present invention, there is provided a lithium ion battery, comprising the above self-healing polymer electrolyte, a positive electrode and a negative electrode.

Preferably, the active material of the positive electrode includes at least one of lithium iron phosphate, lithium cobaltate, lithium manganate, lithium vanadium phosphate, lithium nickel cobalt manganate and lithium nickel cobalt aluminate;

Preferably, the active material of the negative electrode includes at least one of metal lithium flakes, graphite, mesocarbon fibers, mesocarbon microspheres, soft carbon, hard carbon and silicon carbon composite materials.

According to a sixth aspect of the present invention, there is provided the application of the above-mentioned lithium ion battery in electronic equipment, electric tools or electric vehicles;

Preferably, the electronic device is a wearable electronic device.

The present invention provides a self-healing polymer electrolyte matrix comprising inorganic nanometer additives, self-healing polyurethane and other polymers. The reversible effect of furan-maleimide structure in self-healing polyurethane makes the self-healing polymer electrolyte matrix have good self-healing ability; other polymers make the self-healing polymer electrolyte matrix have good ionic conductivity; inorganic nano-additives Active sites are provided, enabling the polymer to easily form a three-dimensional cross-linked structure, which further improves the ionic conductivity.

The self-healing polymer electrolyte containing the self-healing polymer electrolyte matrix has high working voltage, excellent electrochemical performance and good self-healing performance.

The lithium-ion battery obtained from the self-healing polymer electrolyte has good flexibility, self-healing performance and high energy density, and improves the safety and reliability of the flexible lithium-ion battery, enabling it to store and release energy in extreme environments. It has good stability and has broad application prospects in the field of wearable electronic devices.

Detailed ways

The embodiments of the present invention will be described in detail below with reference to the examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. If the specific conditions are not indicated in the examples, it is carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used without the manufacturer's indication are conventional products that can be purchased from the market.

It should be noted:

In the present invention, unless otherwise specified, all the embodiments and preferred implementation methods mentioned herein can be combined with each other to form new technical solutions.

In the present invention, unless otherwise specified, all the technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

In the present invention, unless otherwise specified, percentage (%) or part refers to the weight percentage or weight part of the composition.

In the present invention, unless otherwise specified, the involved components or their preferred components can be combined with each other to form a new technical solution.

In the present invention, unless otherwise stated, the numerical range "a-b" represents an abbreviated representation of any combination of real numbers between a and b, where both a and b are real numbers. For example, the numerical range "0%-10%" means that all real numbers between "0%-10%" have been listed in the text, and "0%-10%" is just an abbreviated representation of the combination of these numerical values.

A "range" disclosed herein may be in the form of a lower limit and an upper limit, which may be one or more lower limits, and one or more upper limits, respectively.

In the present invention, unless otherwise specified, each reaction or operation step can be carried out sequentially or in sequence. Preferably, the reaction methods herein are performed sequentially.

Unless otherwise defined, professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods or materials similar or equivalent to those described can also be used in the present invention.

According to the first aspect of the present invention, a self-healing polymer electrolyte matrix is provided, and the self-healing polymer electrolyte matrix includes inorganic nano-additives, self-healing polyurethane and other polymers;

Among them, inorganic nano-additives and other polymers are grafted on self-healing polyurethane;

Self-healing polyurethane is obtained by the Diels-Alder reaction.

"Other polymers" refers to polymers other than self-healing polyurethane, and are simply referred to as "other polymers".

It should be noted that "inorganic nano-additives and other polymers are grafted on the self-healing polyurethane" means that the inorganic nano-additives react with the isocyanate groups on the self-healing polyurethane to be grafted on the self-healing polyurethane, for example, The inorganic nano-additive can be reacted with the monomer diisocyanate of the polyurethane to obtain a modified inorganic nano-additive, and then the modified inorganic nano-additive, diisocyanate and dihydroxy compound can be reacted to graft the inorganic nano-additive on the polyurethane; other polymerization It can interact with functional groups such as oxygen-containing functional groups to form hydrogen bonds to cross-link with self-healing polyurethane.

"The self-healing polyurethane is obtained by the Diels-Alder reaction" means that the self-healing polyurethane obtained by the Diels-Alder reaction contains dynamic covalent bonds capable of self-healing.

There is no special restriction on the Diels-Alder reaction. For example, it can be a furan/maleimide Diels-Alder cycloaddition reaction. In this case, the self obtained by the furan/maleimide Diels-Alder cycloaddition reaction The repairing polyurethane is a furan-maleimide structure type self-repairing polyurethane, that is, a self-repairing polyurethane with dynamic covalent bonds is obtained by a Diels-Alder reaction between a furan derivative and a maleimide. Self-healing polyurethane realizes self-healing through dynamic covalent bonds, and dynamic covalent bonds are obtained by Diels-Alder reaction between furan derivatives and maleimide derivatives, which is furan-maleimide structural self-healing polyurethane.

It should be noted that the present invention has no special limitation on the source of the inorganic nano-additives, and the inorganic nano-additives known to those skilled in the art that can be used in batteries can be used; for example, it can be graphene oxide, carbon nanotubes, nano-Al ₂ O ₃ , nano-SiO ₂ or nano-TiO ₂ .

It should be noted that the present invention has no special limitation on the source of other polymers, and other polymers known to those skilled in the art that can be used in batteries can be used; for example, it can be PVDF-HFP, PVDF, PEO or PAN any of the above, or a composite material comprising any of the foregoing materials.

PVDF is an abbreviation for polyvinylidene fluoride, PVDF-HFP is an abbreviation for poly(vinylidene fluoride-hexafluoropropylene) copolymer, PEO is an abbreviation for polyethylene oxide, and PAN is an abbreviation for polyacrylonitrile.

The reversible effect of furan-maleimide structure in self-healing polyurethane makes the self-healing polymer electrolyte matrix have good self-healing ability; other polymers make the self-healing polymer electrolyte matrix have good ionic conductivity; inorganic nano-additives Active sites are provided, enabling the polymer to easily form a three-dimensional cross-linked structure, which further improves the ionic conductivity.

In one embodiment, a furan ring graft-modified polyurethane is obtained by grafting a furan derivative onto a polyurethane, and then the furan ring graft-modified polyurethane and a maleimide derivative are subjected to Diels-Alder reaction to obtain self- repair polyurethane;

Among them, the end groups of the polyurethane include isocyanate groups.

"Grafting a furan derivative onto a polyurethane to obtain a furan ring graft-modified polyurethane" means that when a furan derivative reacts with the terminal isocyanate group on the polyurethane, so as to be grafted on the polyurethane, and after the grafting Without destroying the furan ring, the obtained polyurethane contains the furan ring.

There is no particular limitation on the types of furan derivatives, and conventional furan derivatives that can be grafted on the polyurethane without breaking the furan ring after grafting can be used in the art. Furan derivatives include but are not limited to containing functional groups that can react with isocyanate groups on polyurethane, and the reaction does not destroy the furan ring; functional groups that can react with isocyanate groups on polyurethane include but are not limited to amino, hydroxyl or carbamate . For example, furan derivatives include, but are not limited to, 2,5-furandimethanol, trifuryl diol, furfuryl alcohol, furfurylamine, furan ring-terminated polyurethane prepolymers, or 1,6-hexamethylene-bis(2 - furyl methyl carbamate).

The types of maleimide derivatives are not particularly limited, and conventional maleimide derivatives that can undergo Diels-Alder reaction with furan rings can be used in the art. The maleimide derivative may be a hydroxyl-containing monomaleimide or a polymaleimide. Maleimide derivatives include but are not limited to N-hydroxyethylmaleimide, N,N'-(4,4'-methylenediphenyl)bismaleimide, M-600 - Maleamide, D-400-maleamide or T-403-maleamide.

The structural formula of M-600-maleamide is:

The structural formula of D-400-maleamide is:

The structural formula of T-403-maleamide is:

In one embodiment, the furan derivative is 2,5-furandimethanol and/or trifuryl diol.

When using 2,5-furandimethanol and/or trifuryl diol to graft on polyurethane, and then performing Diels-Alder reaction with maleimide derivative to obtain self-healing polyurethane for preparing lithium ion battery, The resulting batteries have more excellent ionic conductivity, cycle times and self-healing properties.

In one embodiment, the maleimide derivative is N-hydroxyethylmaleimide and/or N,N'-(4,4'-methylenediphenyl)bismaleyl imine.

Diels-Alder reaction of N-hydroxyethylmaleimide and/or N,N'-(4,4'-methylenediphenyl)bismaleimide with grafted furan rings on polyurethane When the obtained self-healing polyurethane is used to prepare a lithium ion battery, the obtained battery has more excellent ionic conductivity, cycle times and self-healing performance.

In one embodiment, the inorganic nanoadditive is graphene oxide and the other polymer is PVDF-HFP.

When graphene oxide and PVDF-HFP are grafted on self-healing polyurethane, when used to prepare lithium-ion batteries, the obtained batteries have more excellent ionic conductivity, cycle times and self-healing properties.

In one embodiment, the mass fraction of the inorganic nano-additive is 0%-10%, and the typical but non-limiting mass fraction of the inorganic nano-additive is 0%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 10%.

In one embodiment, the mass fraction of the inorganic nano-additive is 0.5%-5%.

By reasonably adjusting and optimizing the mass fraction of inorganic nano-additives, the obtained self-healing polyurethane can be used to prepare lithium-ion batteries, and the obtained batteries have good ionic conductivity, cycle times and self-healing properties.

In one embodiment, the mass fraction of the inorganic nano-additive is 0.8%-1.5%.

By reasonably adjusting and optimizing the mass fraction of inorganic nano-additives, when the obtained self-healing polyurethane is used to prepare lithium-ion batteries, the obtained batteries have better ionic conductivity, cycle times and self-healing properties.

In one embodiment, the mass fraction of self-healing polyurethane is 30%-60%, preferably 40%-50%; the typical but non-limiting mass fraction of self-healing polyurethane is 30%, 32%, 34%, 36% %, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, or 60%.

In one embodiment, the mass fraction of other polymers is 30%-60%, preferably 40%-50%; the typical but non-limiting mass fractions of other polymers are 30%, 32%, 34%, 36% %, 38%, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58%, or 60%.

According to a second aspect of the present invention, there is provided a method for preparing the above-mentioned self-healing polymer electrolyte matrix, comprising the following steps:

Inorganic nano-additives and other polymers are grafted on the self-healing polyurethane to obtain a self-healing polymer electrolyte matrix.

The self-healing polymer electrolyte matrix can be prepared by grafting inorganic nano-additives and other polymers on the self-healing polyurethane. The preparation method is simple.

In one embodiment, the preparation method of the self-healing polymer electrolyte matrix comprises the following steps:

(a) dissolving the inorganic nano-additive in an organic solvent, then adding diisocyanate, and reacting to obtain a modified inorganic nano-additive;

(b) adding a bishydroxy compound to the solution obtained in step (a), and obtaining a polyurethane grafted with an inorganic nano-additive after the reaction;

(c) adding a furan derivative to the step (b), so that the furan derivative is grafted on the polyurethane obtained in the step (b);

(d) adding the maleimide derivative to the step (c), so that the maleimide derivative and the furan derivative undergo Diels-Alder reaction to obtain a self-repairing polyurethane with dynamic covalent bonds;

(e) dissolving other polymers in an organic solvent, and then adding them to the solution in step (d), so that other polymers are grafted on the self-healing polyurethane obtained in step (d), and coated on the surface of the substrate, and after removing the solvent , to obtain a self-healing polymer electrolyte matrix.

In one embodiment, in step (a), the organic solvent includes an amide organic solvent, preferably N,N-dimethylformamide; the diisocyanate includes 4,4'-methylenebis(isocyanatobenzene) ester), toluene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate and at least one of lysine diisocyanate, preferably 4,4'-methylenebis (phenyl isocyanate); the temperature of the reaction is 75-95°C, the time of the reaction is 2-4h, and the gas atmosphere of the reaction is nitrogen; the feeding ratio of the inorganic nano-additive, organic solvent and diisocyanate is 0-22:40 -60: 6-10 mg/mL/mmol, preferably 20: 50: 8 mg/mL/mmol.

In step (b), the dihydroxy compound includes polyether polyol, preferably polytetrahydrofuran diol, more preferably polytetrahydrofuran diol with a number-average molecular weight of 1500-2500; the reaction temperature is 75-95 ° C, and the reaction time is For 2-4h, the gas atmosphere of the reaction is nitrogen; the molar ratio of the dihydroxy compound to the diisocyanate is 1:1.8-2.5, preferably 1:2.

In step (c), the temperature of grafting is 75-95° C., the time of grafting is 2-4h, and the gas atmosphere for grafting is nitrogen; the molar ratio of furan derivative to diisocyanate is 6-6.5:8, preferably is 6.25:8.

In step (d), the temperature of the reaction is 75-95° C., the time of the reaction is 12-38h, and the gas atmosphere of the reaction is nitrogen; the molar ratio of the maleimide derivative to the furan derivative is 4-4.5:6 -6.5, preferably 4.2:6.25.

In step (e), the organic solvent includes an amide organic solvent, preferably N,N-dimethylformamide, the grafting temperature is 60-100°C, and the grafting time is 1-12h; The weight ratio of repairing polyurethane is 30-60:30-60, preferably 40-50:40-50.

According to a third aspect of the present invention, a self-healing polymer electrolyte is provided, comprising the above-mentioned self-healing polymer electrolyte matrix or the self-healing polymer electrolyte matrix obtained by the above preparation method, an electrolyte salt and a solvent.

The self-healing polymer electrolyte containing the self-healing polymer electrolyte matrix has high working voltage, excellent electrochemical performance and good self-healing performance. The application of the self-healing polymer electrolyte in the battery can make the final battery have good performance. It has excellent flexibility, self-healing performance and high energy density, and improves the safety and reliability of flexible lithium-ion batteries, so that the stability of energy storage and release in extreme environments is better, in the field of wearable electronic devices. has broad application prospects.

The type of electrolyte salt is not particularly limited, and conventional lithium salts that can be used in lithium ion batteries in the art can be used. For example, lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium acetate, lithium salicylate, lithium acetoacetate, lithium carbonate, lithium trifluoromethanesulfonate, lithium dodecyl sulfate, lithium citrate, bismuth Lithium (trimethylsilyl)amide, lithium hexafluoroarsenate or lithium trifluoromethanesulfonimide.

There is no particular limitation on the type of solvent, and conventional organic solvents or ionic liquids that can be used in lithium ion batteries in the art can be used. For example, the organic solvent can be an ester type solvent, a sulfone type solvent, an amide type solvent, an ether type solvent or a nitrile type solvent; the ester type solvent can be propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, carbonic acid Ethyl methyl, butylene carbonate, dipropyl carbonate, propyl methyl carbonate, dibutyl carbonate, butyl methyl carbonate, isopropyl methyl carbonate, methyl methyl, methyl formate, methyl acetate, fluoroethylene carbonate ester, methyl propionate, ethyl propionate, ethyl acetate, gamma-butyrolactone, vinyl sulfite, propylene sulfite, dimethyl sulfite or diethyl sulfite, optionally propylene carbonate , ethylene carbonate, diethyl carbonate, dimethyl carbonate or ethyl methyl carbonate; sulfone solvents can be dimethyl sulfone; amide solvents can be N,N-dimethylacetamide; ether solvents can be Tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, dimethoxymethane, 1,2-dimethoxyethane, 1, 2-dimethoxypropane, triethylene glycol dimethyl ether, dimethyl ether, or crown ether; the ionic liquid can be 1-ethyl-3-methylimidazole-tetrafluoroborate, 1-ethyl-3- Methylimidazole-hexafluorophosphate, 1-ethyl-3-methylimidazole-bis-trifluoromethanesulfonimide salt, 1-propyl-3-methylimidazole-tetrafluoroborate, 1- Propyl-3-methylimidazole-hexafluorophosphate, 1-propyl-3-methylimidazole-bis-trifluoromethylsulfonimide salt, 1-butyl-1-methylimidazole-hexafluorophosphate Salt, 1-butyl-1-methylimidazole-tetrafluoroborate, 1-butyl-1-methylimidazole-bis-trifluoromethanesulfonimide salt, N-butyl-N-methyl Pyrrolidine-bis-trifluoromethanesulfonimide salt, 1-butyl-1-methylpyrrolidine-bis-trifluoromethylsulfonimide salt, N-methyl-N-propylpyrrolidine-bis Trifluoromethylsulfonimide salt, N-methyl, propylpiperidine-bis-trifluoromethylsulfonimide salt or N-methyl, butylpiperidine-bis-trifluoromethylsulfonimide salt. The concentration of the electrolyte salt in the electrolyte is 0.1-10 mol/L.

In one embodiment, the electrolyte salt is lithium hexafluorophosphate.

The self-healing polymer electrolyte obtained with lithium hexafluorophosphate as the electrolyte salt enables the final battery to have good ionic conductivity, cycle times and self-healing properties.

In one embodiment, the concentration of the electrolyte salt in the electrolyte is 1 mol/L.

By reasonably adjusting and optimizing the amount of electrolyte salt added, the final battery can have good ionic conductivity, cycle times and self-healing properties.

According to a fourth aspect of the present invention, there is provided a method for preparing the above-mentioned self-healing polymer electrolyte, comprising the following steps:

The self-healing polymer electrolyte matrix is immersed in a solvent containing electrolyte salt and adsorbed to saturation to obtain a self-healing polymer electrolyte.

The self-healing polymer electrolyte matrix is immersed in a solvent containing electrolyte salt, swelled and activated, adsorbed to saturation, and wiped off excess solvent to obtain the self-healing polymer electrolyte. The preparation method is simple.

According to a fifth aspect of the present invention, there is provided a lithium ion battery, comprising the above self-healing polymer electrolyte, a positive electrode and a negative electrode.

Lithium-ion batteries contain repairing polymer electrolytes, which have good flexibility, self-healing performance and high energy density, and improve the safety and reliability of flexible lithium-ion batteries, enabling them to store and release energy in extreme environments. It has good stability and has broad application prospects in the field of wearable electronic devices.

The type of the active material of the positive electrode is not particularly limited, and the active material of the positive electrode of the lithium ion battery conventional in the art can be used. For example, it can be lithium iron phosphate, lithium cobaltate, lithium manganate, lithium vanadium phosphate, lithium nickel cobalt manganate, or lithium nickel cobalt aluminate.

The type of the active material of the negative electrode is not particularly limited, and the conventional active material in the art that can be used for the negative electrode of a lithium ion battery can be used. For example, it can be metallic lithium flakes, graphite, mesocarbon fibers, mesocarbon microspheres, soft carbon, hard carbon or silicon carbon composites.

The structure and shape of the lithium ion battery is not limited, and it can be a button battery, a cylindrical battery or a soft pack battery.

According to a sixth aspect of the present invention, there is provided an application of the above-mentioned lithium ion battery in an electronic device, an electric tool or an electric vehicle.

The application of the above-mentioned lithium-ion battery in electronic equipment, power tools or electric vehicles can improve the safety and reliability of electronic equipment, power tools or electric vehicles,

In one embodiment, an application of the above lithium-ion battery in a wearable electronic device is provided.

The above-mentioned lithium-ion battery has high safety and reliability, so that it has good energy storage and release stability in extreme environments, and can be used in wearable electronic devices.

The technical solutions of the present invention will be further described below with reference to the examples and comparative examples.

Example 1

1. Self-healing polymer electrolyte matrix

A self-healing polymer electrolyte matrix, including graphene oxide (500nm-2μm in size), self-healing polyurethane and PVDF-HFP (Aldrich, M _w ~ 455000, _Mn ~ 110000); graphene oxide and PVDF-HFP are connected. The branch is on the self-healing polyurethane, and the self-healing polyurethane is a furan-maleimide structure type self-healing polyurethane.

2. Preparation of self-healing polymer electrolyte matrix

The preparation method of the self-healing polymer electrolyte matrix comprises the following steps:

(a) Dissolve 20 mg of graphene oxide in 50 mL of DMF (N,N-dimethylformamide), then add 2.0 g of 4,4'-methylenebis(phenyl isocyanate), at 80°C Under N ₂ protection reaction for 2h, the modified inorganic nano-additive was obtained.

(b) 8.0 g of polytetrahydrofurandiol (PTMEG2000) was added to the solution obtained in step (a), added dropwise to the reaction system through a constant pressure dropping funnel under the protection of N , and the reaction was continued at 80 °C for ₂ h, After the reaction, a polyurethane grafted with inorganic nano-additives is obtained.

(c) 0.8 g of 2,5-furandimethanol was added to step (b), and the reaction was continued for 2 h under _N2 protection at 80 °C to graft the 2,5-furandimethanol obtained in step (b). on polyurethane.

(d) adding 1.5 g of N,N'-(4,4'-methylenediphenyl)bismaleimide (BMI) in step (c), so that BMI is the same as that obtained in step (c). The furan ring on the polyurethane undergoes a Diels-Alder reaction, and the reaction is continued at 80 °C for 24 h under _N2 protection to obtain a self-healing polyurethane with dynamic covalent bonds.

(e) Dissolve 2g of PVDF-HFP in 20mL of DMF, stir at 80°C for 3h to make PVDF-HFP completely dissolve in DMF, then add it to the solution of step (d), stir at 80°C for 2h , so that PVDF-HFP is grafted on the self-healing polyurethane obtained in step (d), the obtained solution is coated on a glass plate, placed in an oven, heated under vacuum at 80 ° C for 24 hours, and the solvent is removed to obtain a self-healing polymer electrolyte matrix.

3. Self-healing polymer electrolyte

A self-healing polymer electrolyte includes a self-healing polymer electrolyte matrix, an electrolyte salt and a solvent.

Preparation of self-healing polymer electrolyte: The self-healing polymer electrolyte matrix was immersed in a mixed solution containing 1M lithium hexafluorophosphate (LiPF ₆ ), swollen and activated, adsorbed to saturation, and wiped off excess solvent to obtain a self-healing polymer electrolyte.

Among them, the mixed solution is a mixed solution composed of EC, EMC and DMC, and their volume ratio is EC:EMC:DMC=1:1:1, and the solution containing electrolyte salt is recorded as 1M LiPF ₆ -EC:EMC:DMC(1 :1:1).

Example 2-5

The only difference between Examples 2-5 and Example 1 is that the types of furan derivatives are different, as shown in Table 1.

Table 1 Types of furan derivatives

Example Types of Furan Derivatives 1 2,5-Furandimethanol 2 furfuryl alcohol 3 furfurylamine 4 1,6-Hexamethylene-bis(2-furylmethylcarbamate) 5 trifuryl glycol

Examples 6-9

The only difference between Examples 6-9 and Example 1 is that the types of maleimide derivatives are different, as shown in Table 2.

Table 2 Types of Maleimide Derivatives

Example Types of Maleimide Derivatives 1 N,N'-(4,4'-methylenediphenyl)bismaleimide 6 N-Hydroxyethylmaleimide 7 M-600-Maleamide 8 D-400-Maleamide 9 T-403-Maleamide

Examples 10-12

The only difference between Examples 10-12 and Example 3 is that the types of other polymers are different, as shown in Table 3.

Table 3 Types of other polymers

Examples 13-16

Examples 13-16 differ from Example 1 only in that the types of inorganic nano-additives are different, as shown in Table 4.

Table 4 Types of inorganic nano-additives

Example Types of Inorganic Nano Additives 1 graphene oxide 13 carbon nanotubes 14 Nano-Al₂O₃ 15 Nano SiO₂ 16 Nano TiO₂

Examples 17-19

Examples 17-19 differ from Example 1 only in that the amount of inorganic nano-additives is different, as shown in Table 5.

Table 5 The dosage of inorganic nano-additives

Example Inorganic nanomaterial additive mass fraction 1 1% 17 0% 18 5% 19 10%

Examples 20-24

Examples 20-24 differ from Example 1 only in that the solvent of the electrolyte salt is different or the concentration of the electrolyte salt is different, as shown in Table 6.

Table 6 Solvents and concentrations of electrolyte salts

Example Solvents and concentrations of electrolyte salts 1 1M LiPF₆-EC:EMC:DMC(1:1:1) 20 1M LiPF₆-EC:DEC(1:1) twenty one 1M LiPF₆-EC:EMC:(1:1) twenty two 1M LiPF₆-EC:DMC:(1:1) twenty three 1M LiPF₆-EC:EMC:DEC(1:1:1) twenty four 1.5M LiPF₆-EC:EMC:DMC(1:1:1)

Comparative Example 1

1. Polymer electrolyte matrix

A polymer electrolyte matrix comprising graphene oxide (500nm-2μm in size), polyurethane and PVDF-HFP (Aldrich, _Mw ～455000, _Mn ～110000); graphene oxide and PVDF-HFP are grafted on polyurethane .

2. Preparation of polymer electrolyte matrix

The preparation method of the polymer electrolyte matrix comprises the following steps:

(a) Dissolve 20 mg of graphene oxide in 50 mL of DMF (N,N-dimethylformamide), then add 2.0 g of 4,4'-methylenebis(phenyl isocyanate), at 80°C Under N ₂ protection reaction for 2h, the modified inorganic nano-additive was obtained.

(b) 8.0 g of polytetrahydrofurandiol (PTMEG2000) was added to the solution obtained in step (a), added dropwise to the reaction system through a constant pressure dropping funnel under the protection of N , and the reaction was continued at 80 °C for ₂ h, After the reaction, a polyurethane grafted with inorganic nano-additives is obtained.

(c) Dissolve 2g of PVDF-HFP in 20mL of DMF, stir at 80°C for 3h to make PVDF-HFP completely dissolve in DMF, then add it to the solution of step (b) and stir at 80°C for 2h , so that PVDF-HFP is grafted on the polyurethane obtained in step (b), the obtained solution is coated on a glass plate, placed in an oven, heated under vacuum at 80 ° C for 24 h, and the solvent is removed to obtain a polymer electrolyte matrix.

3. Polymer electrolyte

A polymer electrolyte includes a polymer electrolyte matrix, an electrolyte salt and a solvent.

Preparation of polymer electrolyte: The polymer electrolyte matrix was immersed in a mixed solution containing 1M lithium hexafluorophosphate (LiPF ₆ ), swelled and activated, adsorbed to saturation, and wiped off excess solvent to obtain a polymer electrolyte.

Among them, the mixed solution is a mixed solution composed of EC, EMC and DMC, and their volume ratio is EC:EMC:DMC=1:1:1, and the solution containing electrolyte salt is recorded as 1M LiPF ₆ -EC:EMC:DMC(1 :1:1).

Test Example 1

1. The self-healing polymer electrolytes prepared in Examples 1-24 and the polymer electrolytes prepared in Comparative Example 1 were tested for electrical conductivity at room temperature. The test method was: assembling a button cell and testing the electrochemical impedance of the polymer electrolyte membrane , and the conductivity is calculated according to the calculation formula ρ=RS/L. The test results are shown in Table 7.

2. The self-healing polymer electrolytes prepared in Examples 1-24 and the polymer electrolytes prepared in Comparative Example 1 were tested for self-healing performance. Heating repair for 1h, the fracture is completely healed, it is repairable, if the fracture is not completely healed, it is irreparable. The test results are shown in Table 7.

3. Assemble the lithium ion battery with the self-healing polymer electrolyte prepared in Examples 1-24 and the polymer electrolyte prepared in Comparative Example 1: Assemble the lithium iron phosphate positive electrode, the self-repairing polymer electrolyte, and the graphite negative electrode in order Assembled into a sandwich structure and sealed on a punch to make a button cell. After standing for 12h, the charging and discharging test was carried out under the conditions of a magnification rate of 0.5C and a voltage of 2.5-4V. The results obtained for the number of cycles (capacity greater than 90%) are shown in Table 7.

Table 7 Ionic conductivity, number of cycles and self-healing performance

The conductivity of the self-healing polymer electrolyte obtained in Example 1 is as high as 2.8×10 ^-3 S/cm, and has a relatively high conductivity at room temperature. The material has good flexibility and good self-healing properties. When the polymer electrolyte is cut in half and heated at 60 °C for 1 h, the fracture is completely healed, and the mechanical properties can reach more than 80% of the previous ones. After 1500 cycles of the battery in Example 1, the capacity retention rate was greater than 90%, indicating that the lithium-ion battery based on the self-healing polymer electrolyte has good electrochemical stability.

According to Examples 1-5, when the furan derivative is 2,5-furandimethanol (Example 1) or trifuryl diol (Example 5), the obtained self-healing polymer electrolyte has more excellent ions Conductivity and self-healing properties, the resulting batteries have more excellent cycle times.

According to Example 1 and Examples 6-9, the maleimide derivative is N,N'-(4,4'-methylenediphenyl)bismaleimide (Example 1) or N-hydroxyethylmaleimide (Example 6), the obtained self-healing polymer electrolyte has more excellent ionic conductivity and self-healing performance, and the obtained battery has more excellent cycle times.

According to Example 1 and Examples 10-12, when the other polymer is PVDF-HFP (Example 1), the obtained self-healing polymer electrolyte has better ionic conductivity and self-healing performance, and the obtained battery has better Excellent cycle times.

According to Example 1 and Examples 13-16, when the inorganic nano-additive is graphene oxide (Example 1), the obtained self-healing polymer electrolyte has better ionic conductivity and self-healing performance, and the obtained battery has better Excellent cycle times.

According to Example 1 and Examples 17-19, when the amount of inorganic nano-additives is 1%-5%, the performance is better, and when the amount of inorganic nano-additives is less than 1% (Example 1), the obtained self-healing polymer The electrolyte has better ionic conductivity and self-healing performance, and the resulting battery has better cycle times.

According to Example 1 and Examples 20-24, the solvent of the electrolyte salt is EC:EMC:DMC (1:1:1) (Example 1) or EC:EMC:DEC (1:1:1) (Example 1) 23), the performance is better, and the performance is better when the electrolyte salt concentration is 1.5M (implementation 24), the self-repairing polymer electrolyte obtained in Example 1 has more excellent ionic conductivity and self-repairing performance, the obtained battery Has more excellent cycle times.

According to Example 1 and Comparative Example 1, it can be seen that the polyurethane of Comparative Example 1 does not contain furan-maleimide dynamic covalent bonds, and the cycle times of the obtained battery are greatly reduced. Example 1 can be cycled 1500 times, while Comparative Example 1 There were only 300 times, and the polymer electrolyte of Comparative Example 1 could not be repaired after fracture.

It should be understood that the content not described in detail in the description of the above preparation method is a common parameter easily thought of by those skilled in the art, and therefore the detailed description thereof can be omitted.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. scope.

Claims (7)

1. A self-healing polymer electrolyte matrix comprising an inorganic nano-additive, a self-healing polyurethane, and other polymers;

wherein the inorganic nano-additive and other polymers are grafted onto the self-healing polyurethane;

the self-repairing polyurethane is obtained through a Diels-Alder reaction;

the Diels-Alder reaction is a furan/maleimide Diels-Alder cycloaddition reaction;

grafting a furan derivative on polyurethane to obtain furan ring graft modified polyurethane, and then carrying out Diels-Alder reaction on the furan ring graft modified polyurethane and a maleimide derivative to obtain self-repairing polyurethane;

wherein the terminal groups of the polyurethane comprise isocyanate groups;

the furan derivative is 2, 5-furandimethanol;

the maleimide derivative is N-hydroxyethyl maleimide;

the inorganic nano additive is graphene oxide;

the other polymer is PVDF-HFP;

the mass fraction of the inorganic nano additive is 1 percent;

the mass fraction of the self-repairing polyurethane is 30-60%;

the mass fraction of the other polymer is 30-60%.

2. The method of making a self-healing polymer electrolyte matrix of claim 1, comprising the steps of:

grafting inorganic nano additive and other polymers on self-repairing polyurethane to obtain a self-repairing polymer electrolyte matrix;

the preparation method of the self-repairing polymer electrolyte matrix comprises the following steps:

(a) dispersing the inorganic nano additive into an organic solvent, then adding diisocyanate, and reacting to obtain a modified inorganic nano additive;

(b) adding a dihydroxy compound into the solution obtained in the step (a), and reacting to obtain polyurethane grafted with an inorganic nano additive;

(c) adding a furan derivative to step (b) to graft the furan derivative onto the polyurethane obtained in step (b);

(d) adding a maleimide derivative into the step (c) to enable the maleimide derivative and a furan derivative to generate Diels-Alder reaction, so as to obtain self-repairing polyurethane with dynamic covalent bonds;

(e) dissolving other polymers in an organic solvent, adding the solution obtained in the step (d) to graft the other polymers on the self-repairing polyurethane obtained in the step (d), coating the self-repairing polyurethane on the surface of the substrate, and removing the solvent to obtain a self-repairing polymer electrolyte matrix;

in the step (a), the organic solvent comprises an amide organic solvent;

and/or, in step (a), the diisocyanate comprises at least one of 4, 4' -methylenebis (phenyl isocyanate), toluene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate;

and/or in the step (a), the reaction temperature is 75-95 ℃, the reaction time is 2-4h, and the reaction gas atmosphere is nitrogen;

and/or, in step (b), the dihydroxy compound comprises a polyether polyol;

and/or in the step (b), the reaction temperature is 75-95 ℃, the reaction time is 2-4h, and the reaction gas atmosphere is nitrogen;

and/or, in step (b), the molar ratio of the dihydroxy compound to the diisocyanate is 1: 1.8-2.5;

and/or in the step (c), the grafting temperature is 75-95 ℃, the grafting time is 2-4h, and the grafting gas atmosphere is nitrogen;

and/or, in step (c), the molar ratio of furan derivative to diisocyanate is 6-6.5: 8;

and/or in the step (d), the reaction temperature is 75-95 ℃, the reaction time is 12-38h, and the gas atmosphere of the reaction is nitrogen;

and/or, in step (d), the molar ratio of maleimide derivative to furan derivative is 4-4.5: 6-6.5;

and/or, in step (e), the organic solvent comprises an amide organic solvent;

and/or, in the step (e), the grafting temperature is 60-100 ℃, and the grafting time is 1-12 h;

and/or, in the step (e), the weight ratio of the other polymer to the self-repairing polyurethane is 30-60: 30-60.

3. A self-repairing polymer electrolyte is characterized by comprising the self-repairing polymer electrolyte matrix of claim 1 or the self-repairing polymer electrolyte matrix prepared by the preparation method of claim 2, an electrolyte salt and a solvent.

4. The self-healing polymer electrolyte of claim 3, wherein the electrolyte salt includes a lithium salt that is at least one of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium acetate, lithium salicylate, lithium acetoacetate, lithium carbonate, lithium trifluoromethanesulfonate, lithium dodecylsulfate, lithium citrate, lithium bis (trimethylsilyl) amide, lithium hexafluoroarsenate, and lithium trifluoromethanesulfonylimide;

the solvent comprises an organic solvent or an ionic liquid;

the organic solvent comprises at least one of an ester solvent, a sulfone solvent, an amide solvent, an ether solvent and a nitrile solvent;

the ester solvent comprises at least one of propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, ethyl methyl carbonate, butylene carbonate, dipropyl carbonate, methyl propyl carbonate, dibutyl carbonate, methyl butyl carbonate, methyl isopropyl carbonate, methyl ester, methyl formate, methyl acetate, fluoroethylene carbonate, methyl propionate, ethyl acetate, gamma-butyrolactone, ethylene sulfite, propylene sulfite, dimethyl sulfite and diethyl sulfite;

the sulfone solvent comprises dimethyl sulfone;

the amide solvent comprises N, N-dimethylacetamide;

the ether solvent comprises at least one of tetrahydrofuran, 2-methyltetrahydrofuran, 1, 3-dioxolane, 4-methyl-1, 3-dioxolane, dimethoxymethane, 1, 2-dimethoxyethane, 1, 2-dimethoxypropane, triethylene glycol dimethyl ether, dimethyl ether and crown ether;

the ionic liquid comprises 1-ethyl-3-methylimidazole-tetrafluoroborate, 1-ethyl-3-methylimidazole-hexafluorophosphate, 1-ethyl-3-methylimidazole-bistrifluoromethylsulfonyl imide salt, 1-propyl-3-methylimidazole-tetrafluoroborate, 1-propyl-3-methylimidazole-hexafluorophosphate, 1-propyl-3-methylimidazole-bistrifluoromethylsulfonyl imide salt, 1-butyl-1-methylimidazole-hexafluorophosphate, 1-butyl-1-methylimidazole-tetrafluoroborate, 1-butyl-1-methylimidazole-bistrifluoromethylsulfonyl imide salt, a salt of a compound of formula (I), At least one of N-butyl-N-methylpyrrolidine-bistrifluoromethylsulfonyl imide salt, 1-butyl-1-methylpyrrolidine-bistrifluoromethylsulfonyl imide salt, N-methyl-N-propylpyrrolidine-bistrifluoromethylsulfonyl imide salt, N-methyl, propylpiperidine-bistrifluoromethylsulfonyl imide salt, and N-methyl, butylpiperidine-bistrifluoromethylsulfonyl imide salt;

the concentration of the electrolyte salt in the electrolyte is 0.1-10 mol/L.

5. The method for preparing the self-repairing polymer electrolyte of claim 3 or 4, which is characterized by comprising the following steps:

and immersing the self-repairing polymer electrolyte matrix in a solvent containing electrolyte salt, and adsorbing until the self-repairing polymer electrolyte matrix is saturated to obtain the self-repairing polymer electrolyte.

6. A lithium ion battery comprising the self-healing polymer electrolyte of claim 3 or 4, a positive electrode, and a negative electrode;

the active material of the positive electrode comprises at least one of lithium iron phosphate, lithium cobaltate, lithium manganate, lithium vanadium phosphate, lithium nickel cobalt manganate and lithium nickel cobalt aluminate;

the active material of the negative electrode comprises at least one of metallic lithium sheets, graphite, mesocarbon fibers, mesocarbon microbeads, soft carbon, hard carbon and silicon-carbon composite materials.

7. Use of the lithium ion battery of claim 6 in an electronic device, an electric tool, or an electric vehicle;

the electronic device is a wearable electronic device.